1. Technical Field
The disclosure generally relates to light emitting diode (LED) lamps, and particularly to an LED lamp with an adjustable illumination direction.
2. Description of Related Art
LEDs (light emitting diodes) are preferred for use in LED lamps rather than CCFLs (cold cathode fluorescent lamps) and other traditional lamps due to their excellent properties, including high brightness, low power consumption, long lifespan, environment friendliness, rapid start-up, directivity, and et al.
Nowadays, screw-type LED lamps are widely used. The screw-type LED lamp is provided with a screw-type lamp cap at one end thereof for electrically connecting the LED lamp with an external power source. Generally, the screw-type LED lamps emit light outwardly around a whole outer circumferential surface thereof. In use, the screw-type lamp cap of the LED lamp is screwed into a screw-type lamp holder which is electrically connected with the external power source, until the screw-type lamp cap is firmly fixed in and electrically connected with the screw-type lamp holder to ensure a good electrical connection between the screw-type lamp cap and the screw-type lamp holder.
However, some screw-type LED lamps are designed to emit light only through a portion of an outer circumferential surface of the LED lamp. Therefore, the screw-type LED lamp is often required to be turned from a first position to a second position so that the emitted light can illuminate on the desired objects at the second position. However, after the screw-type LED lamp is turned from the first position to the second position, the screw-type lamp cap may be electrically disengaged from the screw-type lamp holder to cause an electrical connection between the screw-type LED lamp and the screw-type lamp holder to be interrupted.
Therefore, it is desirable to provide an LED lamp with an illumination direction thereof being adjustable.